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Journal articles on the topic 'ASCIS'

Author: Grafiati
Published: 4 June 2021
Last updated: 19 February 2022

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1

Rudge, Chris, Narcyz Ghinea, Megan Munsie, and Cameron Stewart. "Regulating autologous stem cell interventions in Australia: updated review of the direct-to-consumer advertising restrictions." Australian Health Review 45, no. 4 (2021): 507. http://dx.doi.org/10.1071/ah20217.

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ObjectiveThis paper provides an update and overview of the law governing direct-to-consumer (DTC) advertising of autologous stem cell interventions (ASCIs) in Australia. It follows significant changes to the advertising regulations made in 2018. MethodsThe paper reviews the three primary sources or ‘centres’ of law regulating ASCIs in Australia, together with the relevant guidance documents that supplement these sources. It provides analysis of how the post-2018 advertising regulations, contained in the Therapeutic Goods Act 1989 (Cwlth), apply to all ‘biologicals’, including ASCIs. It demonstrates how these three sources of law interact with one another and outlines the new tiered offence regime that applies to contraventions of these prohibitions. ResultsThe analysis demonstrates that DTC advertising of ASCIs in Australia is strictly controlled, with primary legislation prohibiting the advertising of biologicals altogether. ConclusionsThe polycentric legal regime regulating biologicals in Australia clearly makes DTC advertising of ASCIs unlawful. Health practitioners who promote ASCIs, either online, in print or in other media forms, may be penalised in different ways and by different authorities. What is known about the topic?Although several analyses have examined the regulation of ASCIs in Australia, no analysis has studied the reforms made in 2018 relating to the advertising of biologicals. As such, this analysis contributes a fresh examination of these relatively recent reforms. What does this paper add?This analysis clarifies the effects of these new advertising regulations, providing clear guidance on the relevant legal provisions for the benefit of health practitioners and health professionals more generally. What are the implications for practitioners?Health practitioners, especially those who offer ASCIs, should be aware that civil and criminal penalties are likely to be imposed on individuals who promote biologicals in Australia by any means.
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2

Badenhorst, Marelise, Evert Verhagen, Mike Lambert, Willem van Mechelen, and James Brown. "When This Happens, You Want the Best Care: Players’ Experiences of Barriers and Facilitators of the Immediate Management of Rugby-Related Acute Spinal Cord Injury." Qualitative Health Research 29, no. 13 (March 13, 2019): 1862–76. http://dx.doi.org/10.1177/1049732319834930.

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Most contact sports, including rugby union, carry a risk of injury. Although acute spinal cord injuries (ASCIs) in rugby are rare, the consequences of such injuries are far-reaching. Optimal management of these injuries is challenging, and a detailed understanding of the different barriers and facilitators to optimal care is needed. In this study, we aimed to describe the perception of players, regarding factors related to the optimal immediate management of a catastrophic injury in a developing country with socioeconomic and health care inequities. The most frequently reported barriers were transportation delays after injury and admission to appropriate medical facilities. Other barriers included inadequate equipment, the quality of first aid care, and barriers within the acute hospital setting. Barriers were more prevalent in rural and lower socioeconomic areas. These findings are relevant for all rugby stakeholders and may help shape education, awareness, and future policy around the immediate management of ASCIs.
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3

Meléndez-Martínez, Antonio J., George Britton, Isabel M. Vicario, and Francisco J. Heredia. "Identification of Isolutein (Lutein Epoxide) ascis-Antheraxanthin in Orange Juice." Journal of Agricultural and Food Chemistry 53, no. 24 (November 2005): 9369–73. http://dx.doi.org/10.1021/jf051722i.

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4

Tam, Annie, Ulrich Arnold, Matthew B. Soellner, and Ronald T. Raines. "Protein Prosthesis: 1,5-Disubstituted[1,2,3]triazoles ascis-Peptide Bond Surrogates." Journal of the American Chemical Society 129, no. 42 (October 2007): 12670–71. http://dx.doi.org/10.1021/ja075865s.

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5

Wang, Fei, Lei Feng, Qingguo Tang, Haifeng Liu, and Huimin Liu. "Preparation and Performance ofcis-Polybutadiene Rubber Composite Materials Reinforced by Organic Modified Palygorskite Nanomaterials." Journal of Nanomaterials 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/936838.

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The hydrophilic character of palygorskite has been modified by grafting organic group and controlling surface energy for improving compatibility of palygorskite in rubber matrix using palygorskite ascis-polybutadiene rubber fillers. The effects of coupling modification on the performance ofcis-polybutadiene rubber materials filled with palygorskite were investigated, and the influence of coupling agent dosage on their mechanical properties was also studied. The results indicated that the mechanical performance ofcis-polybutadiene rubber materials reinforced by modified palygorskite could be improved significantly, and the tensile strength and tearing strength increased by 122.5% and 107.6% at the optimal dosage (15%) of coupling agent 3-mercaptopropyl trimethoxysilane. Moreover, the reinforcement mechanism of rubber composite materials as prepared was also analyzed.
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Wang, Fei, Lei Feng, Qingguo Tang, Jinsheng Liang, Haifeng Liu, and Huimin Liu. "Effect of Modified Sepiolite Nanofibers on Properties ofcis-Polybutadiene Rubber Composite Nanomaterials." Journal of Nanomaterials 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/369409.

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In order to use sepiolite nanofibers ascis-polybutadiene rubber fillers, the hydrophilic character of sepiolite nanofibers should be modified by grafting organic group and controlling surface free energy for improving compatibility of sepiolite nanofibers in rubber matrix. The relationship between the performance of thecis-polybutadiene rubber filled with sepiolite and the coupling modification was investigated, and the influence of coupling agentγ-(2,3-epoxypropoxy)propyltrimethoxysilane dosage on mechanical properties ofcis-polybutadiene rubber materials was also studied. The results showed that the mechanical properties could be improved obviously after reinforcement by modified sepiolite nanofibers. The optimum dosage of coupling agentγ-(2,3-epoxypropoxy)propyltrimethoxysilane was 7%, and the tensile strength and tearing strength increased by 108.3% and 74.1%, respectively. On this basis, the reinforcement mechanism of the composite rubber materials was also discussed.
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7

Stimson, Krista M., and Paula M. Vertino. "Methylation-mediated Silencing ofTMS1/ASCIs Accompanied by Histone Hypoacetylation and CpG Island-localized Changes in Chromatin Architecture." Journal of Biological Chemistry 277, no. 7 (December 3, 2001): 4951–58. http://dx.doi.org/10.1074/jbc.m109809200.

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8

Zuo, H. L., F. Q. Yang, X. M. Zhang, and Z. N. Xia. "Separation ofcis- andtrans-Asarone fromAcorus tatarinowiiby Preparative Gas Chromatography." Journal of Analytical Methods in Chemistry 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/402081.

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A preparative gas chromatography (pGC) method was developed for the separation of isomers (cis- andtrans-asarone) from essential oil ofAcorus tatarinowii. The oil was primarily fractionated by silica gel chromatography using different ratios of petroleum ether and ethyl acetate as gradient elution solvents. And then the fraction that contains mixture of the isomers was further separated by pGC. The compounds were separated on a stainless steel column packed with 10% OV-101 (3 m × 6 mm, i.d.), and then the effluent was split into two gas flows. One percent of the effluent passed to the flame ionization detector (FID) for detection and the remaining 99% was directed to the fraction collector. Two isomers were collected after 90 single injections (5 uL) with the yield of 178 mg and 82 mg, respectively. Furthermore, the structures of the obtained compounds were identified ascis- andtrans-asarone by1H- and13C-NMR spectra, respectively.
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9

Swart, Chantel W., Pieter W. J. van Wyk, Carolina H. Pohl, and Johan L. F. Kock. "Variation in yeast mitochondrial activity associated with asci." Canadian Journal of Microbiology 54, no. 7 (July 2008): 532–36. http://dx.doi.org/10.1139/w08-036.

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An increase in mitochondrial membrane potential (ΔΨm) and mitochondrially produced 3-hydroxy (3-OH) oxylipins was experienced in asci of the nonfermentative yeasts Galactomyces reessii and Lipomyces starkeyi and the fermentative yeasts Pichia farinosa and Schizosaccharomyces octosporus . Strikingly, asci of Zygosaccharomyces bailii showed no increase in mitochondrial activity (ΔΨm and oxylipin production). As expected, oxygen deprivation only inhibited ascus formation in those yeasts with increased ascus mitochondrial activity. We conclude that ascus formation in yeasts is not always dependent on mitochondrial activity. In this case, fermentation may provide enough energy for ascus formation in Z. bailii.
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10

Raju, Namboori B., David D. Perkins, and Dorothy Newmeyer. "Genetically determined nonselective abortion of asci in Neurospora crassa." Canadian Journal of Botany 65, no. 7 (July 1, 1987): 1539–49. http://dx.doi.org/10.1139/b87-212.

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In many crosses of laboratory strains of Neurospora crassa, a large proportion of complete asci abort shortly after ascospore delimitation. The aborted asci contain eight small, degenerate, vacuolated ascospores. We use the term "bubble asci" to signify this special form of ascus abortion. The frequency of bubble asci was scored in 8- to 10-day-old perithecia from crosses between closely related strains and between unrelated strains. When two unrelated or distantly related strains are mated, fewer than 10% of asci abort, whereas up to 70% or more of the asci abort when inbred strains are mated to each other. We conclude that the degree of genetic relatedness of the two haploid parents determines whether abortion occurs. Progeny tests indicate that several genes are involved; the simplest interpretation is that they are weak deleterious recessives whose effects must be combined to produce a high frequency of bubble asci. No ascospores survive in the aborted asci. Therefore, bubble asci cannot distort allele ratios of markers among surviving progeny. When a dominant Round-spore gene was present in one parent of a high bubble-ascus cross, none of the young bubble asci contained nonround spores. Therefore, bubble asci do not result from illegitimate fusion of two nuclei of the same mating type. Heterokaryon-incompatibility genes are not involved in producing bubble asci. No or little bubble-ascus abortion occurs in the homothallic or pseudohomothallic species of Neurospora.
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11

Olivier, Andries P. S., Chantel W. Swart, Carolina H. Pohl, Pieter W. J. van Wyk, Hendrik C. Swart, Elizabeth Coetsee, Schalk W. Schoombie, Jon Smit, and Johan Lodewyk F. Kock. "The “firing cannons” of Dipodascopsis uninucleata var. uninucleata." Canadian Journal of Microbiology 59, no. 6 (June 2013): 413–16. http://dx.doi.org/10.1139/cjm-2013-0130.

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According to literature, the elongated ascospores of Dipodascopsis uninucleata var. uninucleata exhibit smart movement when forcefully ejected from bottle-shaped asci. This type of movement is defined as the unique patterns of non-random movement of ascospores with specialized morphology thereby facilitating release from asci. Smart movement is required to actively release ascospores individually through the narrow ascus neck, without causing an obstruction and blocking ascospore release. However, little is known about the propulsion mechanism of this cannon-type release system. We show that asci of this yeast contain a central channel (barrel) filled with ascospores. These are surrounded by a sheath-like structure that lines the inner surface of the ascus wall. We found that this sheath is responsible for forcing the naked ascospores out of the ascus by exerting turgor pressure from the bottom towards the tip of the ascus. This cannon firing system is in contrast to that found in Dipodascus geniculatus, where no sheaths lining the ascus interior were observed. Instead, sheaths were found enveloping each ascospore.
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12

Perkins, David D., and Namboori B. Raju. "Three-to-one segregation from reciprocal translocation quadrivalents in Neurospora and its bearing on the interpretation of spore-abortion patterns in unordered asci." Genome 38, no. 4 (August 1, 1995): 661–72. http://dx.doi.org/10.1139/g95-084.

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In Neurospora, viable ascospores become black (B) when mature, whereas ascospores that are deficient for a chromosome segment are inviable and usually fail to blacken. The presence of a chromosome rearrangement can be recognized and the type of rearrangement can usually be inferred by visual inspection of asci. When a cross is heterozygous for a reciprocal translocation, asci with eight black ascospores (8B:0W) and asci with eight abortive unpigmented ("white" (W)) ascospores (0B:8W) are theoretically produced in equal numbers if homologous centromeres are equally likely to segregate from the quadrivalent in alternate or adjacent modes. In addition, 4B:4W asci are produced with a frequency characteristic of each reciprocal translocation. Information on ascospore-abortion patterns in Neurospora crassa has come predominantly from unordered ascospore octads ejected from the perithecium. Unordered asci of the 4B:4W type were initially presumed to originate by interstitial crossing over in a centromere-breakpoint interval and their frequency was used as a predictor of centromere locations. However, 4B:4W asci can result not only from interstitial crossing over but also from nondisjunction of centromeres at the first meiotic division, which leads to 3:1 segregation. Ordered linear 4B:4W asci retain the sequence information necessary for distinguishing one mode of origin from the other but unordered asci do not. Crossing over results in one abortive duplication–deficiency ascospore pair in each opposite half of a linear ascus, while 3:1 segregation places both abortive ascospore pairs together, either in the distal half or the basal half of the ascus. In the present study, perithecia were opened and intact linear asci were examined in crosses heterozygous for a varied sample of translocations. Three-to-one segregation rather than interstitial crossing over is apparently the main cause of 4B:4W asci when breakpoints are near centromeres, whereas crossing over is responsible for most or all 4B:4W asci when breakpoints are far-distal. Three-to-one segregation does not impair the usefulness of ejected unordered asci for detecting chromosome rearrangements. Ejected octads are superior to ordered linear asci for distinguishing one type of rearrangement from another, because ascus ejection from the perithecium does not occur until viable ascospores are fully pigmented, enabling true 0B:8W asci to be distinguished from those with eight immature ascospores.Key words: ascospore abortion, ascus analysis, Neurospora, nondisjunction, reciprocal translocation, three-to-one segregation.
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13

Liang, Qianwa, Jian-Sen He, and Armand J. Fulco. "The Role of Barbie Box Sequences ascis-Acting Elements Involved in the Barbiturate-mediated Induction of Cytochromes P450BM−1and P450BM−3inBacillus megaterium." Journal of Biological Chemistry 270, no. 9 (March 3, 1995): 4438–50. http://dx.doi.org/10.1074/jbc.270.9.4438.

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14

Moody, Joanna D., James P. Freeman, Daniel R. Doerge, and Carl E. Cerniglia. "Degradation of Phenanthrene and Anthracene by Cell Suspensions of Mycobacterium sp. Strain PYR-1." Applied and Environmental Microbiology 67, no. 4 (April 1, 2001): 1476–83. http://dx.doi.org/10.1128/aem.67.4.1476-1483.2001.

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ABSTRACT Cultures of Mycobacterium sp. strain PYR-1 were dosed with anthracene or phenanthrene and after 14 days of incubation had degraded 92 and 90% of the added anthracene and phenanthrene, respectively. The metabolites were extracted and identified by UV-visible light absorption, high-pressure liquid chromatography retention times, mass spectrometry, 1H and 13C nuclear magnetic resonance spectrometry, and comparison to authentic compounds and literature data. Neutral-pH ethyl acetate extracts from anthracene-incubated cells showed four metabolites, identified ascis-1,2-dihydroxy-1,2-dihydroanthracene, 6,7-benzocoumarin, 1-methoxy-2-hydroxyanthracene, and 9,10-anthraquinone. A novel anthracene ring fission product was isolated from acidified culture media and was identified as 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid. 6,7-Benzocoumarin was also found in that extract. When Mycobacterium sp. strain PYR-1 was grown in the presence of phenanthrene, three neutral metabolites were identified as cis- andtrans-9,10-dihydroxy-9,10-dihydrophenanthrene andcis-3,4-dihydroxy-3,4-dihydrophenanthrene. Phenanthrene ring fission products, isolated from acid extracts, were identified as 2,2′-diphenic acid, 1-hydroxynaphthoic acid, and phthalic acid. The data point to the existence, next to already known routes for both gram-negative and gram-positive bacteria, of alternative pathways that might be due to the presence of different dioxygenases or to a relaxed specificity of the same dioxygenase for initial attack on polycyclic aromatic hydrocarbons.
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15

Richardson, Jane S., Christopher J. Williams, Bradley J. Hintze, Vincent B. Chen, Michael G. Prisant, Lizbeth L. Videau, and David C. Richardson. "Model validation: local diagnosis, correction and when to quit." Acta Crystallographica Section D Structural Biology 74, no. 2 (February 1, 2018): 132–42. http://dx.doi.org/10.1107/s2059798317009834.

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Traditionally, validation was considered to be a final gatekeeping function, but refinement is smoother and results are better if model validation actively guides corrections throughout structure solution. This shifts emphasis from global to local measures: primarily geometry, conformations and sterics. A fit into the wrong local minimum conformation usually produces outliers in multiple measures. Moving to the right local minimum should be prioritized, rather than small shifts across arbitrary borderlines. Steric criteria work best with all explicit H atoms. `Backrub' motions should be used for side chains and `P-perp' diagnostics to correct ribose puckers. A `water' may actually be an ion, a relic of misfitting or an unmodeled alternate. Beware of wishful thinking in modeling ligands. At high resolution, internally consistent alternate conformations should be modeled and geometry in poor density should not be downweighted. At low resolution,CaBLAMshould be used to diagnose protein secondary structure andERRASERto correct RNA backbone. All atoms should not be forced inside density, beware of sequence misalignment, and very rare conformations such ascis-non-Pro peptides should be avoided. Automation continues to improve, but the crystallographer still must look at each outlier, in the context of density, and correct most of them. For the valid few with unambiguous density and something that is holding them in place, a functional reason should be sought. The expectation is a few outliers, not zero.
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16

Xue, Zhixiong, Xiaoyin Shan, Alex Sinelnikov, and Teri Melese. "Yeast Mutants That Produce a Novel Type of Ascus Containing Asci Instead of Spores." Genetics 144, no. 3 (November 1, 1996): 979–89. http://dx.doi.org/10.1093/genetics/144.3.979.

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Abstract Tetraploid yeast cells lacking BFR1 or overexpressing an essential gene BBPl produce a novel type of ascus that contains asci instead of spores. We show here that the asci within an ascus likely arise because a/α spores undergo a second round of meiosis. Cells depleted of Bbplp or lacking Bfr1p are defective in a number of processes such as nuclear segregation, bud formation, cytokinesis and nuclear spindle formation. Furthermore, deletion of BFR1 or overexpression of BBP1 leads to an increase in cell ploidy, indicating that Bfr1p and Bbplp play roles in both the mitotic cell cycle and meiosis. Bfr1p and Bbp1p interact with each other in a two hybrid assay, further suggesting that they might form a complex important for cell cycle coordination.
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17

Wyk, P. W. J. van, and M. J. Wingfield. "Ascospore development in Ophiostoma piceae." Canadian Journal of Botany 70, no. 11 (November 1, 1992): 2170–76. http://dx.doi.org/10.1139/b92-268.

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The development of ascoma, ascus, and ascospore in Ophiostoma piceae was studied ultrastructurally and compared with that of other Ascomycetes. Ascospore delimitation commenced with the formation of double delimiting membranes in the ascus. The ascospore wall, consisting of the primary and secondary walls, was deposited between these membranes. The elongate ascospores of O. piceae differed from other species having similarly shaped ascospores, with respect to the shape and arrangement of asci in the ascoma, the number of wall layers of the ascospore, and formation of the secondary wall. Asci in O. piceae are spindle shaped, arranged along the periphery of the ascomatal wall. The ascospores have three layered walls, whereas some other species in Ceratocystis s.l. also with elongated ascospores probably have only two wall layers. Key words: Ophiostoma, elongated ascospores, sheaths, centrum.
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18

Ncango, Desmond M., Carolina H. Pohl, Olihile M. Sebolai, Piet J. Botes, Catharina J. Strauss, Manjusha Joseph, Pieter W. J. Van Wyk, Santosh Nigam, and Johan L. F. Kock. "Oxylipin-coated hat-shaped ascospores of Ascoidea corymbosa." Canadian Journal of Microbiology 52, no. 11 (November 1, 2006): 1046–50. http://dx.doi.org/10.1139/w06-069.

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We previously implicated 3-hydroxy oxylipins and ascospore structure in ascospore release from enclosed asci. Using confocal laser scanning microscopy on cells stained with fluorescein-coupled, 3-hydroxy oxylipin-specific antibodies, we found that oxylipins are specifically associated with ascospores and not the vegetative cells or ascus wall of Ascoidea corymbosa. Using gas chromatography – mass spectrometry the oxylipin 3-hydroxy 17:0 could be identified. Here, we visualize for the first time the forced release of oxylipin-coated, hat-shaped ascospores from terminally torn asci, probably through turgor pressure. We suggest that oxylipin-coated, razor-sharp, hat-shaped ascospore brims may play a role in rupturing the ascus to affect release.Key words: Ascoidea corymbosa, ascospore release, confocal laser scanning microscopy, gas chromatography – mass spectrometry, hat-shaped ascospores, 3-hydroxy oxylipins.
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Citterio, Barbara, Manuela Malatesta, Serafina Battistelli, Francesco Marcheggiani, Wally Baffone, Roberta Saltarelli, Vilberto Stocchi, and Giancarlo Gazzanelli. "Possible involvement ofPseudomonas fluorescensand Bacillaceae in structural modifications ofTuber borchiifruit bodies." Canadian Journal of Microbiology 47, no. 3 (March 1, 2001): 264–68. http://dx.doi.org/10.1139/w01-005.

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Previous studies on Tuber borchii fruit bodies in early maturation stages suggested a role of bacteria in sporocarp structural modifications. In order to verify this hypothesis, in the present study we investigated by means of microbial and ultrastructural approaches, the bacterial population of T. borchii sporocarps from intermediate maturation phases to advanced decomposition stages, paying particular attention to chitinolytic and cellulolytic bacteria and to their relationships with ascii and ascospores. We found that Pseudomonas fluorescens and spore-forming Bacillaceae, both able to degrade cellulose and chitin, are present inside the sporocarps in all maturation stages investigated. Moreover, rod-shaped bacteria seem able to erode ascus walls and colonize the interior of ascii containing mature spores. These results suggest a possible role of these bacteria in the process of ascus opening. Moreover, the presence of P. fluorescens and Bacillaceae on isolated mature spores after decontamination suggests an intimate association between these bacteria and the ascospores.Key words: bacteria, cellulose, chitin, ectomycorrhiza.
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20

Kaulmann, Ursula, Stefan R. Kaschabek, and Michael Schlömann. "Mechanism of Chloride Elimination from 3-Chloro- and 2,4-Dichloro-cis,cis-Muconate: New Insight Obtained from Analysis of Muconate Cycloisomerase Variant CatB-K169A." Journal of Bacteriology 183, no. 15 (August 1, 2001): 4551–61. http://dx.doi.org/10.1128/jb.183.15.4551-4561.2001.

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ABSTRACT Chloromuconate cycloisomerases of bacteria utilizing chloroaromatic compounds are known to convert 3-chloro-cis,cis-muconate tocis-dienelactone (cis-4-carboxymethylenebut-2-en-4-olide), while usual muconate cycloisomerases transform the same substrate to the bacteriotoxic protoanemonin. Formation of protoanemonin requires that the cycloisomerization of 3-chloro-cis,cis-muconate to 4-chloromuconolactone is completed by protonation of the exocyclic carbon of the presumed enol/enolate intermediate before chloride elimination and decarboxylation take place to yield the final product. The formation ofcis-dienelactone, in contrast, could occur either by dehydrohalogenation of 4-chloromuconolactone or, more directly, by chloride elimination from the enol/enolate intermediate. To reach a better understanding of the mechanisms of chloride elimination, the proton-donating Lys169 of Pseudomonas putida muconate cycloisomerase was changed to alanine. As expected, substrates requiring protonation, such ascis,cis-muconate as well as 2- and 3-methyl-, 3-fluoro-, and 2-chloro-cis,cis-muconate, were not converted at a significant rate by the K169A variant. However, the variant was still active with 3-chloro- and 2,4-dichloro-cis,cis-muconate. Interestingly,cis-dienelactone and 2-chloro-cis-dienelactone were formed as products, whereas the wild-type enzyme forms protoanemonin and the not previously isolated 2-chloroprotoanemonin, respectively. Thus, the chloromuconate cycloisomerases may avoid (chloro-)protoanemonin formation by increasing the rate of chloride abstraction from the enol/enolate intermediate compared to that of proton addition to it.
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21

Kimbrough, James W., and Jack L. Gibson. "Ultrastructural and cytological observations of apothecial tissues of Geopyxis carbonaria (Pezizales, Ascomycetes)." Canadian Journal of Botany 68, no. 2 (February 1, 1990): 243–57. http://dx.doi.org/10.1139/b90-034.

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Cytological observations are made on apothecial tissues of Geopyxis carbonaria, using transmission electron microscopy. Characteristic features of both the medullary and ectal excipula are examined. Changes in ascus apex and wall structures are examined during ascus ontogeny, especially in relation to operculum position and structure. Ultrastructure of septum configuration is observed and compared in the excipulum, ascogenous hyphae, paraphyses, and at the base of young asci. Ascosporogenesis is observed from the ascus mother cell stage and initial spore delimitation until secondary wall formation. The cytological and ultrastructural observations on this species are discussed in relation to their possible taxonomic or phylogenetic value. Key words: ascosporogenesis, Discomycetes, ascospore ultrastructure, septal ultrastructure, cytochemistry.
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22

Gurjar, Mukund K., Radhika D. Wakharkar, Anu T. Singh, Manu Jaggi, Hanumant B. Borate, Popat D. Shinde, Ritu Verma, et al. "Synthesis and Evaluation of 4/5-Hydroxy-2,3-diaryl(substituted)-cyclopent-2-en-1-ones ascis-Restricted Analogues of Combretastatin A-4 as Novel Anticancer Agents." Journal of Medicinal Chemistry 50, no. 8 (April 2007): 1744–53. http://dx.doi.org/10.1021/jm060938o.

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23

Encinar del Dedo, Javier, Encarnación Dueñas, Yolanda Arnáiz, Francisco del Rey, and Carlos R. Vázquez de Aldana. "β-Glucanase Eng2 Is Required for Ascus Wall Endolysis after Sporulation in the Fission Yeast Schizosaccharomyces pombe." Eukaryotic Cell 8, no. 8 (June 19, 2009): 1278–86. http://dx.doi.org/10.1128/ec.00148-09.

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ABSTRACT Meiosis is the developmental program by which sexually reproducing diploid organisms generate haploid gametes. In yeast, meiosis is followed by spore morphogenesis. When Schizosaccharomyces pombe diploid cells undergo meiosis, they differentiate into asci containing four haploid ascospores that are highly resistant to environmental stress. The formation of the ascospore wall requires the activity of several enzymes involved in the biosynthesis and modification of its components, such as α- and β-glucan synthases. Once the spores are completely mature, the wall of the ascus undergoes an endolytic process that results in the release of ascospores from the ascus, allowing their dispersal into the environment. This process requires the activity of the endo-α-1,3-glucanase Agn2. Here, we focus on the characterization of the endo-β-1,3-glucanase Eng2, which is also required for ascospore release from the ascus. Although Eng2 is present during the mitotic cycle, the protein accumulates after meiosis II. The expression of eng2 + is required for the efficient release of ascospores, as shown by placing eng2 + under the control of a repressible promoter. Furthermore, a point mutation that destroys the catalytic activity of the protein results in a phenotype similar to that of the mutant strain. Finally, we demonstrate that exogenous addition of purified Eng2 releases the ascospores from asci generated by an eng2Δ mutant. We propose that Eng2 would act together with Agn2 to completely hydrolyze the ascus wall, thereby assisting in the release of ascospores in S. pombe.
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Hallen, Heather E., and Frances Trail. "The L-Type Calcium Ion Channel Cch1 Affects Ascospore Discharge and Mycelial Growth in the Filamentous Fungus Gibberella zeae (Anamorph Fusarium graminearum)." Eukaryotic Cell 7, no. 2 (December 14, 2007): 415–24. http://dx.doi.org/10.1128/ec.00248-07.

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ABSTRACT Cch1, a putative voltage-gated calcium ion channel, was investigated for its role in ascus development in Gibberella zeae. Gene replacement mutants of CCH1 were generated and found to have asci which did not forcibly discharge spores, although morphologically ascus and ascospore development in the majority of asci appeared normal. Additionally, mycelial growth was significantly slower, and sexual development was slightly delayed in the mutant; mutant mycelia showed a distinctive fluffy morphology, and no cirrhi were produced. Wheat infected with Δcch1 mutants developed symptoms comparable to wheat infected with the wild type; however, the mutants showed a reduced ability to protect the infected stalk from colonization by saprobic fungi. Transcriptional analysis of gene expression in mutants using the Affymetrix Fusarium microarray showed 2,449 genes with significant, twofold or greater, changes in transcript abundance across a developmental series. This work extends the role of CCH1 to forcible spore discharge in G. zeae and suggests that this channel has subtle effects on growth and development.
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25

Wyk, P. W. J. van, and M. J. Wingfield. "Ultrastructural study of ascoma and ascospore development in Ophiostoma distortum and Ophiostoma minus." Canadian Journal of Botany 69, no. 11 (November 1, 1991): 2529–38. http://dx.doi.org/10.1139/b91-315.

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The development of the ascoma, ascus, and elongated ascospores in Ophiostoma distortum and Ophiostoma minus was studied at the ultrastructural level and compared with that of other related Ascomycetes. The organization of the centra in O. distortum and O. minus differed considerably. In O. distortum, asci were irregularly arranged in clusters that occurred in the lower half along the periphery of the ascoma. In O. minus, asci developed from a central cluster at the base of the ascoma. The asci extended upwards and outwards from the base. Ascospore development in both fungi commenced with the formation of double, delimiting membranes in the ascus. Between these membranes ascospore walls developed, consisting of the primary and secondary wall. In comparison with other species having similar ascospores, differences were found between the number of wall layers of the ascospores and formation of the outer wall layers. The secondary wall and perisporic sac of O. minus were smooth and of uniform thickness, whereas the inner layer of the secondary wall in O. distortum was thickened and distorted in certain areas. It is suggested that additional ultrastructural studies should be undertaken to provide a better understanding of the development and evolution of ascospore sheaths in Ceratocystis sensu lato. Key words: Ceratocystis, elongated ascospores, centrum.
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26

Belhadj-Tahar, Hafid, Pierre Payoux, Mathieu Tafani, Yvon Coulais, Serge Calet, and Azzedine Bousseksou. "Toxicological Methods for Tracing Drug Abuse: Chromatographic, Spectroscopic and Biological Characterisation of Ecstasy Derivatives." Archives of Industrial Hygiene and Toxicology 61, no. 1 (March 1, 2010): 53–59. http://dx.doi.org/10.2478/10004-1254-61-2010-1937.

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Toxicological Methods for Tracing Drug Abuse: Chromatographic, Spectroscopic and Biological Characterisation of Ecstasy DerivativesAnalysis often reveals variability in the composition of ecstasy pills from pure 3,4-methylenedioxymethamphetamine (MDMA) to mixtures of MDMA derivatives, amphetamine, and other unidentified substances. For a comprehensive toxicological analysis one needs to know all steps to MDMA synthesis which may originate impurities. The aim of this study was to synthesise and determine the chemical-physical andin vitrobiological properties of a series of MDMA derivatives.3,4-methylendioxyphenyl-2-nitropropene (MDNP) was obtained by condensation of piperonal with an excess of nitroethane in the presence of ammonium acetate. MDNP was then reduced to methylenedioxyamphetamine (MDA) by LiAlH3. All compounds were analysed using HPLC and spectroscopic technique [Raman, nuclear magnetic resonance (NMR), or infrared (IR)] at all the steps of synthesis. In addition, we assessed the biological potentials of these compounds by measuringin vitrotheir (i) blood cell/whole blood partition coefficient, (ii) binding to plasmatic proteins (Fbp), and (iii) membrane adsorption. Chemical structure was determined with antibody fluorescence polarisation immunoassay (FPIA). This study showed the presence of solid impurities, particularly of a neurotoxic compound of Al3+in the final products. FPIA identified the aminoethane group close to the substituted benzene ring, but did not detect the two major precursors of MDMA: MDNP and piperonal. Raman spectroscopy is an attractive alternative technique to characterise ecstasy pills and it can identify stereoisomeric forms such ascis-MDNP andtrans-MDNP, which exhibit signals at 1650 cm-1and 1300 cm-1, respectively.
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Wong, Sze-Wing, Kevin D. Hyde, Wai-Hong Ho, and Susan J. Stanley. "Tamsiniella labiosa gen. et sp.nov., a new freshwater ascomycete from submerged wood." Canadian Journal of Botany 76, no. 2 (February 1, 1998): 332–37. http://dx.doi.org/10.1139/b98-007.

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Investigations into the fungi occurring on wood submerged in freshwater ecosystems have revealed a unique, but characteristic group of fungi. In this paper a new pyrenomycete, Tamsiniella labiosa gen. et sp.nov., is described and illustrated with light, scanning, and transmission electron micrographs. The genus has remarkable short stipitate cylindrical asci with an internal refractive apical ring that are apically truncate and have an external thickening. Ascospores are ellipsoidal-fusiform and surrounded by a mucilaginous sheath. At the transmission electron microscope level, the annulus part of the ascus apical apparatus is differentiated from the inner ascus wall layer and is composed of horizontally oriented, electron-dense fibrillar material. A narrow plug is present in the centre of the apical ring. An electron-dense amorphous region occurs between the outer ascus wall layer and the annulus part of the apical apparatus. The outer ascus wall layer is lacking at the apex. The ultrastructure of the ascus apex differs from those described in the Lasiosphaeriaceae, Sordariaceae, and Xylariaceae.Key words: aquatic fungi, Myelosperma, new genus, transmission electron microscope.
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28

Corde, S., M. C. Biston, H. Elleaume, F. Estève, A. M. Charvet, A. Joubert, V. Ducros, et al. "Lack of Cell Death Enhancement after Irradiation with Monochromatic Synchrotron X Rays at the K-Shell Edge of Platinum Incorporated in Living SQ20B Human Cells ascis-Diamminedichloroplatinum (II)." Radiation Research 158, no. 6 (December 2002): 763–70. http://dx.doi.org/10.1667/0033-7587(2002)158[0763:locdea]2.0.co;2.

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29

Raju, Namboori B., and John F. Leslie. "Cytology of recessive sexual-phase mutants from wild strains of Neurospora crassa." Genome 35, no. 5 (October 1, 1992): 815–26. http://dx.doi.org/10.1139/g92-124.

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Wild-collected strains of Neurospora crassa harbor recessive mutations that are expressed in the sexual phase when homozygous. Thirty-two representative mutants that produced barren perithecia were examined cytologically. Six of these mutants failed to form asci. Of the remaining 26, chromosome pairing was disturbed in 12 and meiosis was disturbed at pachytene or diplotene in 5. Seven mutants showed normal meiosis I but then diverged from the normal sequence, and two showed perithecial beak abnormalities. In many mutants, ascus development and nuclear divisions continued after the initial defect, albeit abnormally. Nuclear divisions were often delayed, essentially uncoupling them from other ascus events such as the formation of enlarged spindle pole body plaques, ascospore wall membranes, and spore delimitation. All 32 mutants were recessive and none showed obvious morphological abnormalities during vegetative growth. This phenotype contrasts sharply with that of numerous laboratory-induced ascus mutants, which are frequently expressed pleiotropically in the vegetative phase and several are dominant in the sexual phase.Key words: natural populations, sexual phase, recessive mutations, meiotic mutants, ascus development.
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30

Quinn, Charles T., Robert C. McKinstry, Michael M. Dowling, William S. Ball, Michael A. Kraut, James F. Casella, Nomazulu Dlamini, et al. "Acute Silent Cerebral Ischemia Occurs More Frequently Than Silent Cerebral Infarction In Children with Sickle Cell Anemia." Blood 116, no. 21 (November 19, 2010): 268. http://dx.doi.org/10.1182/blood.v116.21.268.268.

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Abstract Abstract 268 Background: Children with sickle cell anemia (HbSS) are at high risk of overt stroke and clinically silent cerebral infarction (SCI). SCI is an infarct-like lesion visualized on magnetic resonance imaging (MRI) of the brain that produces no corresponding motor or sensory deficits. The prevalence of SCI in HbSS is approximately 20 – 30% by 16 years of age, but less is known about its incidence. The Cooperative Study of Sickle Cell Disease (CSSCD) found the incidence of new or more extensive SCI in children with HbSS to be 7 events per 100 patient-years. Given that SCI is clinically silent, the only way to determine its incidence (the number of new events occurring in a specific time-period) is to screen with two sequential MRIs of the brain. MRI can also detect acute cerebral ischemia in asymptomatic patients using diffusion-weighted imaging (DWI). The incidence of acute silent cerebral ischemic events (ASCIEs) is not known. A clinical trial setting provides a unique opportunity to determine the incidence of ASCIEs and SCI in children with HbSS. Objectives: To determine the incidence rates of (1) ASCIEs in children with HbSS without prior evidence of focal neurological deficits and (2) new, recurrent SCI in children with HbSS who have pre-existing SCI. Methods: We studied a cohort of children with HbSS and sickle-β0-thalassemia who had brain MRIs for the Silent Infarct Transfusion Trial. All participants had no prior history of overt stroke, seizures, or transient ischemic attacks. ASCIE was defined as an infarct-like lesion on brain MRI without corresponding motor or sensory deficits that appeared as a focus of T2 hyperintensity with restricted diffusion on DWI sequences. SCI was defined an infarct-like lesion without corresponding motor or sensory deficits that appeared as a focus of T2 hyperintensity without restricted diffusion. Given that acute cerebral ischemia appears as a focus of restricted diffusion on DWI for 10 days, we assumed that each MRI scan provided 10 patient-days of observation for detecting ASCIE. Therefore, the incidence of ASCIEs was calculated using a single MRI per patient. The incidence of new or more extensive SCI in children with pre-existing SCI was determined in those who had two MRIs each (screening and pre-randomization). We statistically compared the incidence rates of ASCIEs and SCI obtained by these two different methods. For all ASCIEs and new SCI events, a medical history tool was completed at the local site at the time of MRI of the brain. Results: In total, 972 MRIs were studied (745 screening, 227 pre-randomization). There were 844 MRIs with DWI sequences, providing 23.1 patient-years of observation in 640 children (52% male; mean age 9.7 years). ASCIEs were detected on 1.2% (10 of 844 MRIs), corresponding to an incidence of 43.3 (95% CI: 20.7 – 79.6) events per 100 patient-years. Nine of the 10 ASCIEs were detected incidentally; 1 ASCIE occurred in a participant who was recovering from a recent episode of acute chest syndrome (onset 5 days before MRI) complicated by severe anemia and hypertension. Standard neurological examination was normal in all cases. Two of the 10 participants with ASCIEs had follow-up MRIs of the brain 4 to 10 months later; one had SCI in the same location as the previously detected acute ischemia, but the other had no residual lesion in the same location. Thus, not all ASCIEs produce detectable SCI. A total of 220 participants (55% male; mean age 10.0 years) had both screening and pre-randomization MRIs. The mean interval between the two MRIs was 124.3 days (range: 14 – 645), providing 74.9 patient-years of observation. All screening MRIs showed baseline SCI. New, recurrent SCI was detected on pre-randomization MRI in 8 participants, corresponding to an incidence of 10.7 events per 100 patient-years (95% CI: 4.6 – 21.0). The incidence of ASCIEs was 4-fold higher than recurrent SCI (43.2 vs. 10.7 events per 100 patient-years; P=0.001). Conclusions: The incidence of recurrent SCI was similar to CSSCD findings. However, we show that children with HbSS experience acute cerebral ischemic events far more frequently than previously recognized. These acute ischemic events are mostly clinically silent, potentially reversible radiographically, and not associated with antecedent medical events. Disclosures: No relevant conflicts of interest to declare.
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31

Perkins, David D., Namboori B. Raju, Virginia C. Pollard, Joseph L. Campbell, and Adam M. Richman. "Use of Neurospora Spore killer strains to obtain centromere linkage data without dissecting asci." Canadian Journal of Genetics and Cytology 28, no. 6 (December 1, 1986): 971–81. http://dx.doi.org/10.1139/g86-135.

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Use of a centromere-linked Spore killer gene Sk reduces manyfold the labor involved in obtaining tetrad data that would otherwise require ordered dissection of intact linear eight-spored asci. Heterozygous crosses are made for Spore killer (SkK × SkS) and for markers to be tested. In such crosses only SkK ascospores survive. The four viable (SkK) and four aborted (SkS) ascospores of each ascus are ejected from the perithecium as a physically disordered group. The four surviving SkK ascospores of individual asci are germinated and scored. SkK segregates from SkS at the first meiotic division. If both marker alleles are represented in the surviving products, they must therefore have segregated from one another at the second division. Four-spore (Fsp) genes have been used to eliminate one postmeiotic nuclear division, so that only two ascospores per ascus need to be scored. The Spore killer method has been useful for mapping closely linked genes in centromere regions, for identifying genes that are far out on chromosome arms, for obtaining information on meiotic crossing-over, and for comparing linkages in different species.Key words: tetrad analysis, centromere mapping, Spore killer, Neurospora.
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32

KUMAR, ARUN. "From Henley to Harvard at Hyderabad? (Post and Neo-) Colonialism in Management Education in India." Enterprise & Society 20, no. 2 (February 18, 2019): 366–400. http://dx.doi.org/10.1017/eso.2018.86.

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Founded in 1956, the Administrative Staff College of India (ASCI) was established with the objective of professionalizing management in post-colonial India through training, research, and consultancy. It was modeled on the Administrative Staff College at Henley-on-Thames (Henley), in the United Kingdom. Like Henley, ASCI used syndicates for its management training programs. Between 1958 and 1973, ASCI received more than $1.26 million from the Ford Foundation, part of which was used to finance the development and use of the case method in ASCI’s training programs, and later more widely in its research and consultancy. This article traces the ways by which the Ford Foundation––as adominating institution––stigmatized Henley and ASCI, their institutional practices, and the wider Indian society; and legitimized the case method pioneered at the Harvard Business School. Imbricated in the Cold War’s geo-politics, Ford Foundation’s interventions in Hyderabad should be understood as part of the emergence of the United States as the dominant neo-colonial power, which required the displacement of Britain, its institutions, and their practices as the template for India’s post-colonial management institutions.
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33

Nelson, Mary Anne, Sandra T. Merino, and Robert L. Metzenberg. "A Putative Rhamnogalacturonase Required for Sexual Development of Neurospora crassa." Genetics 146, no. 2 (June 1, 1997): 531–40. http://dx.doi.org/10.1093/genetics/146.2.531.

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In previous work, the asd-1 (ascus development) gene of the filamentous fungus Neurospora crassa was identified as a gene expressed preferentially during the sexual cycle and shown to be essential for normal sexual development. The asd-1 gene has been sequenced and further characterized. It contains two introns, the first of which is in-frame and inefficiently or differentially spliced. The predicted ASD-1 protein has extensive homology with rhamnogalacturonase B of Aspergillus aculeatus, which cleaves the backbone within the ramified hairy regions of pectin. In homozygous asd-1 crosses, sexual development is initiated and large numbers of normal-sized asci are formed. Ascospore delineation does not occur, however, and no sexual progeny are produced. As most asd-1 asci contain eight nuclei, the two meiotic divisions and subsequent mitotic division typical of normal crosses seem to occur, but the haploid nuclei are not partitioned into ascospores. In wild-type crosses, the ASD-1 protein is present in large amounts in croziers and young asci, but it is only faintly detectable in more mature asci containing developing ascospores. Models to explain the possible role of a rhamnogalacturonase in sexual development are presented.
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34

Linke, Michael J., Alan Ashbaugh, Margaret S. Collins, Keeley Lynch, and Melanie T. Cushion. "Characterization of a Distinct Host Response Profile to Pneumocystis murina Asci during Clearance of Pneumocystis Pneumonia." Infection and Immunity 81, no. 3 (January 14, 2013): 984–95. http://dx.doi.org/10.1128/iai.01181-12.

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ABSTRACTPneumocystisspp. are yeast-like fungi that cause pneumocystis pneumonia (PcP) in immunocompromised individuals and exacerbate chronic lung diseases in immunocompetent individuals. ThePneumocystislife cycle includes trophic forms and asci (cyst forms). The cell walls ofPneumocystisasci contain β-1,3-d-glucan, and treatment of PcP with β-1,3-d-glucan synthase inhibitors, such as anidulafungin, results in depletion of asci, but not trophic forms. The pulmonary host response during immune reconstitution (IR)-mediated clearance of PcP in anidulafungin-treated and untreated mice was characterized to identify ascus-specific responses. During IR, similar numbers of trophic forms were present in the anidulafungin-treated and untreated mice; however, asci were only present in the untreated mice. IR resulted in a significant reduction of trophic forms from the lungs in both groups and asci in the untreated group. The presence of asci in untreated mice correlated with increased β-glucan content in the lungs. The untreated mice mounted immune responses associated with a deleterious host inflammatory response, including increased CD8+T cell influx and expression of macrophage inflammatory response markers. A more robust cellular response was also observed in the untreated mice, with increased numbers of macrophages and neutrophils that were associated with greater lung damage. Markers of a Th17 response were also elevated in the untreated mice. These results suggest that the host mounts unique responses to asci and trophic forms. That these 2 life cycle stages provoked distinct host response profiles has significant implications for clearance and interpretation of the host immune responses to PcP.
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35

Shiu, Patrick K. T., and Robert L. Metzenberg. "Meiotic Silencing by Unpaired DNA: Properties, Regulation and Suppression." Genetics 161, no. 4 (August 1, 2002): 1483–95. http://dx.doi.org/10.1093/genetics/161.4.1483.

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Abstract In Neurospora, a gene not paired with a homolog in prophase I of meiosis generates a signal that transiently silences all sequences homologous to it by a process called meiotic silencing by unpaired DNA (MSUD). Thus a deletion mutation in a heterozygous cross is formally “ascus-dominant” because its unpaired wild-type partner silences itself. We describe in detail the isolation of a mutation, Sad-1UV, that suppresses the dominance of various ascus-dominant mutations. Additional dominant, semidominant, and recessive Sad-1 alleles have been generated by RIP; the DNA of the dominant RIP alleles becomes methylated, but dim-2-dependent methylation is not necessary for silencing. The barrenness of homozygous Sad-1 crosses is not due to the failure to silence unpaired mating-type mat A-2 mat A-3 genes. Transcripts of sad-1+ can be detected during the sexual phase in a homozygous wild-type cross, indicating that the gene is expressed even if all DNA can pair normally. Meiotic silencing is confined to the ascus in which DNA is unpaired, and silencing does not spread to neighboring asci in a fruiting body of mixed genetic constitution.
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36

VALADBEIGI, Tahereh, Matthias SCHULTZ, and Wolfgang VON BRACKEL. "Two new species of Lichenothelia (Lichenotheliaceae) from Iran." Lichenologist 48, no. 3 (May 2016): 191–99. http://dx.doi.org/10.1017/s0024282916000104.

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AbstractTwo new species of Lichenothelia, both from Iran, are described. Lichenothelia iranica is characterized by a black thallus with often finely lobate, slightly effigurate, not areolate margins, eight non-amyloid spores per ascus and 1–3-septate ascospores with 1–2 longitudinal or oblique septa. Lichenothelia ilamensis is distinguished by a black areolate, fissured, slightly effigurate or rarely lobulate thallus. The areoles are confluent and aggregated in the centre, becoming dispersed towards the margin, and the asci contain (4–)6(–8) non-amyloid, 1-septate spores.
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37

ALVES, Marilia Muryel Estevam, André APTROOT, Sírleis Rodrigues LACERDA, and Marcela Eugenia da Silva CÁCERES. "Three newArthoniaceaefrom Chapada do Araripe, Ceará, NE Brazil." Lichenologist 46, no. 5 (August 7, 2014): 663–67. http://dx.doi.org/10.1017/s0024282914000206.

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AbstractThree new corticolousArthoniaceaeare described from the Chapada do Araripe, an isolated table mountain in the state of Ceará, in NE Brazil.Arthonia stipitata, lichenicolous on unidentified sorediate crusts, with red, tiny, stipitate apothecia, 3-septate ascospores, 10–12×3·0–3·5 µm.Stirtonia lucidawith rather small ascigerous areas, lichexanthone and zeorin in the thallus, globose asci, ascospores 8 per ascus, ellipsoid, 17–19×8–10 µm, with occasionally some longitudinal septa.Stirtonia ochraceawith rather small ochraceous ascigerous areas, thallus without secondary metabolites, ascospores 8 per ascus, (7–)9(–11)-septate, 47–55×14–20 µm. These species were found during a study aiming at an inventory of the lichen biodiversity of the Cerrado forests in the area, and were not found during earlier ecological studies in the Caatinga forests in the same area.Stirtonia lucidais the first species assigned to this genus which occasionally has some longitudinal septa in the ascospores. Such specimens might be confused withCryptotheciaspecies.
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38

Bażant, J. "Observations on the occurrence of Erysiphales on cucumbers in Poland." Acta Mycologica 20, no. 1 (August 20, 2014): 63–69. http://dx.doi.org/10.5586/am.1984.006.

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In the years 1974-79 in Skierniewice and in 12 other places <i>Erysiphe cichoracearum </i>DC (imperfect stage) was observed on cucumbers in 1979 both <i>A. cichoraceum</i> and <i>Sphaerotheca fuliginea</i> were found in Skierniewice, Zielonka and Gołębiewo. Then were distinguished in the conidial stage mainly on the basis of differences in conidial germination and the presence or absence of fibrous bodies, and in the perfect stage on the basis of the number of asci in peridia and the number of spores per ascus.
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39

Ulrych, Oldrich. "ASCII Editor pro TeX." Zpravodaj Československého sdružení uživatelů TeXu 1, no. 1 (1991): 10–12. http://dx.doi.org/10.5300/1991-1/10.

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40

Wagner, Marisa, Peter Briza, Michael Pierce, and Edward Winter. "Distinct Steps in Yeast Spore Morphogenesis Require Distinct SMK1 MAP Kinase Thresholds." Genetics 151, no. 4 (April 1, 1999): 1327–40. http://dx.doi.org/10.1093/genetics/151.4.1327.

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Abstract The SMK1 mitogen-activated protein kinase is required for spore morphogenesis in Saccharomyces cerevisiae. In contrast to the multiple aberrant spore wall assembly patterns seen even within a single smk1 null ascus, different smk1 missense mutants block in a coordinated fashion at intermediate stages. One smk1 mutant forms asci in which the four spores are surrounded only by prospore wall-like structures, while another smk1 mutant forms asci in which the spores are surrounded by inner but not outer spore wall layers. Stepwise increases in gene dosage of a hypomorphic smk1 allele allow for the completion of progressively later morphological and biochemical events and for the acquisition of distinct spore-resistance phenotypes. Furthermore, smk1 allelic spore phenotypes can be recapitulated by reducing wild-type SMK1 expression. The data demonstrate that SMK1 is required for the execution of multiple steps in spore morphogenesis that require increasing thresholds of SMK1 activity. These results suggest that quantitative changes in mitogen-activated protein kinase signaling play a role in coordinating multiple events of a single cellular differentiation program.
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41

Hamer, J. E., B. Valent, and F. G. Chumley. "Mutations at the smo genetic locus affect the shape of diverse cell types in the rice blast fungus." Genetics 122, no. 2 (June 1, 1989): 351–61. http://dx.doi.org/10.1093/genetics/122.2.351.

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Abstract Teflon film surfaces are highly conducive to the formation of infection structures (appressoria) in the plant pathogenic fungus, Magnaporthe grisea. We have utilized Teflon films to screen and select for mutants of M. grisea that are defective in appressorium formation. This approach and several others yielded a group of 14 mutants with a similar phenotype. All the mutant strains make abnormally shaped conidia and appressoria. When two mutant strains are crossed, abnormally shaped asci are formed. Ascus shape is normal when a mutant strain is crossed with a wild-type strain. Despite dramatic alterations in cell shape these strains otherwise grow, form conidia, undergo meiosis, and infect plants normally. This mutant phenotype, which we have termed Smo(-), for abnormal spore morphology, segregates in simple Mendelian fashion in crosses with wild-type strains. Some ascospore lethality is associated with smo mutations. In genetic crosses between mutants, smo mutations fail to recombine and do not demonstrate complementation of the abnormal ascus shape phenotype. We conclude that the smo mutations are alleles of a single genetic locus and are recessive with regard to the the ascus shape defect. Mutations at the SMO locus also permit germinating M. grisea conidia to differentiate appressoria on surfaces that are not normally conducive to infection structure formation. A number of spontaneous smo mutations have been recovered. The frequent occurrence of this mutation suggests that the SMO locus may be highly mutable.
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42

Ireland, Stanley. "Aspis." Classical Review 49, no. 2 (October 1999): 354–56. http://dx.doi.org/10.1093/cr/49.2.354.

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43

Philippa-Touchais, Anna, and Gilles Touchais. "Aspis." Bulletin de correspondance hellénique 130, no. 2 (2006): 714–21. http://dx.doi.org/10.3406/bch.2006.7788.

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44

Chen, Hung-Hsuan, and C. Lee Giles. "ASCOS++." ACM Transactions on Knowledge Discovery from Data 10, no. 2 (October 26, 2015): 1–26. http://dx.doi.org/10.1145/2776894.

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45

Frable, William J. "ASCUS! ASCUS! down the rabbit hole." Cancer 87, no. 6 (December 25, 1999): 319–21. http://dx.doi.org/10.1002/(sici)1097-0142(19991225)87:6<319::aid-cncr1>3.0.co;2-0.

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46

Czymmek, Kirk J., and Karen L. Klomparens. "The ultrastructure of ascosporogenesis in freeze-substituted Thelebolus crustaceus: enveloping membrane system and ascospore initial development." Canadian Journal of Botany 70, no. 8 (August 1, 1992): 1669–83. http://dx.doi.org/10.1139/b92-206.

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High-pressure and propane-jet freezing were essential for determining the origin and development of the enveloping membrane system during ascosporogenesis in Thelebolus crustaceus. Prior to the completion of mitotic divisions within the ascus, invaginations of the plasma membrane initiated formation of the enveloping membrane system. Fusion of individual units of the closely spaced double membranes resulted in the formation of a cylinder around most of the ascus protoplasm. This double-membraned cylinder enveloped individual nuclei with accompanying cytoplasm and organelles to form ascospore initials. Envelopment of asci nuclei to form ascospore initials appeared to be facilitated by a nuclear-associated organelle and closely associated microtubule organizing center. Initially, wall materials and (or) precursors were deposited between the closely spaced double membranes from within the ascospore initials. Secondary wall formation appeared to be deposited, in part, from the epiplasm. Microtubules located adjacent to the inside wall layer of the ascospore initials appeared to contribute to an elliptical shape. Subsequent to epispore wall formation, numerous microtubules were found associated with the outer membranes of the ascospores and appeared to interconnect the spores into a single mass before discharge. Key words: Thelebolus crustaceus, ascosporogenesis, high-pressure freezing, propane-jet freezing, ultrastructure, laser scanning confocal microscopy.
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47

Read, Susan J., E. B. Gareth Jones, and Stephen T. Moss. "Taxonomic studies of marine Ascomycotina: ultrastructure of the asci, ascospores, and appendages of Savoryella species." Canadian Journal of Botany 71, no. 2 (February 1, 1993): 273–83. http://dx.doi.org/10.1139/b93-028.

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The asci, ascospores, and appendages of Savoryella longispora, Savoryella paucispora, and Savoryella appendiculata were examined at the transmission electron microscope level. Asci of S. longispora and S. appendiculata have a well-developed apical apparatus that consists of a thickened electron-dense ring with a central pore. In S. appendiculata the pore is occluded by a plug of electron-lucent material. The ascus wall comprises an outer narrow electron-opaque layer and an inner electron-lucent layer that are continuous over the apical apparatus. Ascospore walls possess an inner electron-lucent mesosporium and an outer electron-opaque episporium. The episporium of the central cells of all three species is covered with a layer of fibrillar mucilage. Granular strand-like outgrowths of the ascospore wall are present on the polar cells of S. appendiculata and S. paucispora. In all three species the hyaline polar cells of the ascospore contain organelles and in S. appendiculata the polar cells are verrucose. Ascospore appendages are only found in S. appendiculata and these arise endogenously by outgrowth of the endosporium of the polar cell. The differences between the three species are not considered significant at the generic level and therefore all are assigned to the genus Savoryella. Key words: appendages, Ascomycotina, ascospores, marine, taxonomy, ultrastructure.
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48

Gonçalves, Erika. "Entrevista: Orly Zucatto Mantovani de Assis." Ensino em Re-vista 25, no. 1 (August 30, 2018): 209–15. http://dx.doi.org/10.14393/er-v25n1a2018-09.

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49

Kutty, Geeta, Shweta Gupta, and Marin Sekosan. "Chronic recurrent biliary ascites: An unusual scenario." Scripta Medica 45, no. 2 (2014): 78–80. http://dx.doi.org/10.5937/scrimed1402078k.

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50

Raju, N. B., and D. D. Perkins. "Expression of meiotic drive elements Spore killer-2 and Spore killer-3 in asci of Neurospora tetrasperma." Genetics 129, no. 1 (September 1, 1991): 25–37. http://dx.doi.org/10.1093/genetics/129.1.25.

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Abstract It was shown previously that when a chromosomal Spore killer factor is heterozygous in Neurospora species with eight-spored asci, the four sensitive ascospores in each ascus die and the four survivors are all killers. Sk-2K and Sk-3K are nonrecombining haplotypes that segregate with the centromere of linkage group III. No killing occurs when either one of these killers is homozygous, but each is sensitive to killing by the other in crosses of Sk-2K x Sk-3K. In the present study, Sk-2K and Sk-3K were transferred by recurrent backcrosses from the eight-spored species Neurospora crassa into Neurospora tetrasperma, a pseudohomothallic species which normally makes asci with four large spores, each heterokaryotic for mating type and for any other centromere-linked genes that are heterozygous in the cross. The action of Sk-2K and Sk-3K in N. tetrasperma is that predicted from their behavior in eight-spored species. A sensitive nucleus is protected from killing if it is enclosed in the same ascospore with a killer nucleus. Crosses of Sk-2K x Sk-2S, Sk-3K x Sk-3S, and Sk-sK x Sk-3K all produce four-spored asci that are wild type in appearance, with the ascospores heterokaryotic and viable. The Eight-spore gene E, which shows variable penetrance, was used to obtain N. tetrasperma asci in which two to eight spores are small and homokaryotic. When killer and sensitive alleles are segregating in the presence of E, only those ascospores that contain a killer allele survive. Half of the small ascospores are killed. In crosses of Sk-2K x Sk-3K (with E heterozygous), effectively all small ascospores are killed. The ability of N. tetrasperma to carry killer elements in cryptic condition suggests a possible role for Spore killers in the origin of pseudohomothallism, with adoption of the four-spored mode restoring ascospore viability of crosses in which killing would otherwise occur.
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